EF-S 18-55mm 1:3.5-5.6 IS STM will not mount on 6D camera

[billrodriguez1]

EF-S 18-55mm 1:3.5-5.6 IS STM lens will not mount on 6D camera.

[cicopo · Accepted solution]

You need to understand the relationship between your 18-55 lens & how it acts on the crop bodies it's designed to fit. It has a smaller light path because the crop bodies have a smaller sensor & gives a similar ratio of image a lens 1.6 times longer does on a full frame body. There isn't a full frame 18-55 but if there was it would be 18 X 1.6 which is 28 mm to 55 X 1.6 = 88 mm so you'd be looking for roughly a 28 - 90 lens BUT it will be physically bigger & heavier.

This may also help explain it a bit.

http://forums.usa.canon.com/t5/Lenses/Using-a-lens-designed-for-crop-bodies-on-full-frame-SAMPLES/m-...

[cicopo]

LUCKY you. It's designed NOT TO because the mirror in a full frame camera may hit the back of the lens & be damaged.

[billrodriguez1]

Is there a 18-55mm lense that will work?

[cicopo]

NO. You now need to shop for lenses with an EF mount or specifically designed for full frame cameras. Tamron & Sigma lenses for crop bodies usually fit the EF mount BUT your photos look like you shot through a pipe.

[cicopo · Accepted solution]

You need to understand the relationship between your 18-55 lens & how it acts on the crop bodies it's designed to fit. It has a smaller light path because the crop bodies have a smaller sensor & gives a similar ratio of image a lens 1.6 times longer does on a full frame body. There isn't a full frame 18-55 but if there was it would be 18 X 1.6 which is 28 mm to 55 X 1.6 = 88 mm so you'd be looking for roughly a 28 - 90 lens BUT it will be physically bigger & heavier.

This may also help explain it a bit.

http://forums.usa.canon.com/t5/Lenses/Using-a-lens-designed-for-crop-bodies-on-full-frame-SAMPLES/m-...

[billrodriguez1]

Great information. THANK YOU for help and input. I am sorry it took so long to THANK YOU!

[ebiggs1 · Accepted solution]

"Is there a 18-55mm lense that will work?"  

This is not a very good lens in the first place.  There are many more that are a much better solution for a EOS 6D.

First choice would be the EF 24-70mm f4 IS USM.  It is going to show you nearly tha same "window" as the 18-55mm.

It is vastly superior.  

Not quite as expensive is the EF 28-135mm f3.5-5.6 IS USM.  Another great choice.  This is a real work horse that has been tried and tested in the Canon line for a very long time.  It simply works.

And the best buy in all of Canon lenses is the EF 24-105mm f4 IS USM.  You can find this lens in what is called a "white box".  Sometimes in the $700-$800 area.  It is a brand new, with full warranty, lens from a Canon kit.  They are also easy to find in great shape used.

Yes, all these sugestions are more expensive that a 18-55mm but there is simply no comparison in quality.  They do not match the focal length exactly but they are close.

[billrodriguez1]

THANK YOU for your help. I apologize in taking so long to thank you.

[TCampbell]

No "EF-S" lens will mount on the 6D -- nor should you try.  

The standard lenses for full-frame digitial and 35mm film cameras are the "EF" lenses.  

Canon's Rebel series bodies as well as the xxD series bodies (70D, 60D, 50D, etc.) and the 7D body all use a physically smaller sensor than the one you have on your 6D.   The sensor size on those cameras is referred to as an "APS-C" size sensor.  APS-C stands for "Advanced Photo System - Classic".  This was a type of drop-in cartridge film used in the 80's.  A single frame of negative on that film was a bit smaller than single frame of film negative on a 35mm camera.  

The lens has to project an image into the inside of the camera which is large enough to cover the sensor from corner to corner.  Since a full-frame camera (like your 6D) has a bigger sensor, it requires a lens that projects a larger image circle.  An APS-C camera has a smaller sensor, so it does not technically "require" a large image circle.  You can still project a large image circle into the camera -- but more of it will spill off the sides of the sensor and the camera will just use the bit that lands on the sensor in the middle of the circle.

As such... Canon reasonsed that they could build lenses that project smaller image circles for these cameras that have smaller sensors.  Since the lens doesn't have to project a large circle, it can use smaller elements (saving weight).  Also light wavelengths disperse as they pass through glass at an angle (like a prism) and the edges of a lens work like a prism.  To counter this effect, additional elements are needed to "undo the damage".  But the physically larger the element, the more of a problem this is.  This means the lenses designed for smaller cameras can not only use smaller elements, they also have less of a dispersion problem and that means they may also get away with having fewer lens elements.   All this reduces the cost and weight of the lens while not actually sacrificing image quality.  The whole point of the small sensor camera was to save money and make cameras that were a bit more affordable.

HOWEVER... if you have a physically larger sensor, you tend to get MUCH BETTER low-light performance and reduce noise at high ISOs.  This is because the sensor is covered with tiny little "photo-sites" which gather light.  These photo-sites on the sensor can be physically larger, making it easier for them to collect photons of light.  More photons = more sensitive = less noise.

Your 6D will "blow the doors off" any camera that has an APS-C or smaller size sensor in terms of it's low-light performance.  Your camera can actually focus at -3EV (it is one of the very best in the industry at dealing with low light situations.)

But... your full-frame sensor means you cannot use the smaller EF-S lenses... you must use the larger EF lenses.

Fortunately, most of the lenses (as well as all of the very BEST lenses) are "EF" lenses.

Enjoy your 6D!

[billrodriguez1]

I apologize in getting to THANK YOU for your input. Great Help!